Circular dichroism and absorption studies of (-)-2,2′-dimethyl-4,5-(1-naphthyl)-1,3-dioxolane in terms of vibronic coupling theory

✍ Scribed by Marcin Makowski; Mariusz Pilch; Marek T. Pawlikowski

• Publisher: John Wiley and Sons
• Year: 2002
• Tongue: English
• Weight: 283 KB
• Volume: 14
• Category: Article
• ISSN: 0899-0042
• DOI: 10.1002/chir.10048

✦ Synopsis

Abstract

The absorption and circular dichroism (CD) spectra of (‐)‐2,2′‐dimethyl‐4,5‐(1‐naphthyl)‐1,3‐dioxolane (DND) were studied in the energy region 30,000 cm^−1^ to 50,000 cm^−1^. The DND ketal is treated as a naphthalene dimer and its spectra are interpreted in terms of a vibronic dimer model which includes the ^1^L~a~ and ^1^B~b~ states of the naphthalene chromophore. To fix the most stable conformation of DND molecule, the MNDO/AM1, RHF/6‐31G, and SVWN5, BPW91 methods are employed with 6‐31G and 6‐31G(d',p') basis sets. All the methods are shown to yield the DND geometry that is entirely consistent with the CD and absorption spectra studied. Chirality 14:274–283, 2002. © 2002 Wiley‐Liss, Inc.